Recent Posts

1

Microcontrollers / Re: Attiny1606 burning out when connected to a drv8251

« Last post by lavaman on Today at 07:46:00 pm »

Thanks for your answers. After some iterations thanks to your recommendations the attiny completely stopped overheating and the circuit is working absolutely fine. But for one fatal exception, the attiny doesn't seem to be able to switch the B input of the drv high. Not sure why tho. All i have done was, directly connect ground to the drv and add 1k ohm resistors between the attiny and input of the drv. One of the inputs can be controlled fully, but the other (input B) cannot be controlled at all and is constantly pulled down, probably by the integrated pulldown resistors of the drv.

2

Microcontrollers / Re: Dim OLED Screen replacement for Agilent Keysight U1253A U1253B U1273A U1273AX

« Last post by onesystem on Today at 07:44:35 pm »

Or did you update through the header here?

Yep, I used it there too.

3

Microcontrollers / Re: Dim OLED Screen replacement for Agilent Keysight U1253A U1253B U1273A U1273AX

« Last post by onesystem on Today at 07:42:09 pm »

I am definitely sure. Later on I even posted that I got a FDTI USB to UART from Amazon which I connected directly and was able to use that connection for uploading of firmware using the stock Keysight/Agilent firmware uploader. It definitely detected the meter and cycled through the update process without problems.

4

Microcontrollers / Re: STM32 interrupt priority

« Last post by DavidAlfa on Today at 07:36:37 pm »

16 levels.
Read RM0008, page 197.

5

Projects, Designs, and Technical Stuff / Re: DIY Digital Caliper

« Last post by MitkoDyakov on Today at 07:35:37 pm »

You can find the all I have here: https://github.com/MitkoDyakov/BluePillCaliper/

Documents - are all written I could find on the subject, patents, paper, work done by others.
Hardware - the footprints for the t-scale and sensor and also gerbers and schematics
Software - I need to update that but, for the software I have written just the excitation of the pads and the display.

   

6

Microcontrollers / Re: ELM327 (serial to OBDII CANbus converter) discontinued

« Last post by DavidAlfa on Today at 07:29:09 pm »

Try contacting them?

https://www.obdsol.com/contact-us/
https://www.scantool.net/contact/

stn21xx controllers have a lead time of 52 weeks!
https://www.obdsol.com/solutions/chips/stn2100/
https://www.obdsol.com/solutions/chips/stn2120/

7

Test Equipment / Re: DMM Input Capacitance

« Last post by 2N3055 on Today at 07:27:13 pm »

Josh,

Those measurements seem very low. Try using your DE-5000 instead at 10KHz like we did. You can use short banana plugs & cables directly with DE-5000, and plug the negative DE-5000 end into your power supply Green ground terminal like 2N3055 did, or just connect to something that has earth ground.

No need to calibrate the DE-5000, we are just looking for relative capacitance, cable capacitance and such shouldn't matter.

Best,

I agree these are very low. It might be because LCR meter is mains powered.
I also want to see DE-5000, which is handheld like my UNI-T.

Floobydust made some good points..

8

Microcontrollers / Re: STM32 interrupt priority

« Last post by kendricks on Today at 07:24:35 pm »

sorry for another question, dont want to create a similar thread

How many interrupts with a higher preempt priority can occur successive? How many steps?

9

Power/Renewable Energy/EV's / Synchronous Buck with Schottky anti-parallel to Synch FET?

« Last post by Faringdon on Today at 07:24:30 pm »

Hi,
Why do they bother with the SMA Schottky in this Synch Buck. (B360A-13-F)?
At the currents being switched , the internal diode in the Sync FET will have a lower vf than that Schottky, so its pretty much a waste of time?

D4 shows Schottky:
https://www.ti.com/lit/df/tidmb83/tidmb83.pdf?ts=1713876988568&ref_url=https%253A%252F%252Fwww.ti.com%252Ftool%252FPMP31210

B360A-13-F
https://www.mouser.co.uk/datasheet/2/115/DIOD_S_A0002833511_1-2542242.pdf

10

Test Equipment / Re: DMM Input Capacitance

« Last post by Sariel on Today at 07:23:15 pm »

Why is a DMM with very low input capacitance favoured?